"At this point unfortunately we won't be able to go any further," the official said, forecasting that China can expect to receive a positive appraisal at Wednesday's summit in The Hague.

The EU embargo was slapped on China after the 1989 Tiananmen Square massacre, but some EU states -- notably France and Germany -- argue that it is outdated.

Dutch Foreign Minister Ben Bot, whose country holds the EU's rotating presidency, said last month that the 25-nation bloc was ready to give a "positive signal" about lifting the ban on weapons sales.

But Bot said that conditions for lifting the ban include progress by China on human rights, while the EU is still working to tighten up a code of conduct to govern an eventual resumption of arms sales.

A positive signal "doesn't mean a decision to lift it (this week), it means that we are working in that direction", the EU official said on condition of anonymity.

The official noted that China had made some "small signals" that it was committed to improving human rights, including a pledge to sign an international covenant on civil and political rights.

"But that is not going to do the trick. We want progress across the board."

European Commission chief Jose Manuel Barroso meanwhile said that Wednesday's summit will be a chance to "further strengthen (the) maturing strategic partnership" between the EU and Beijing.